LILIANA (LILY) WOLAK
MD Candidate (2024) | University of British Columbia
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Student Feedback
"[Lily's] warm & agreeable disposition allows us to engage & answer questions without any pressure"
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"[Lily is] good at taking very complex matters & breaking them down into a simpler way to understand them"
"[Lily] explains things clearly and tries her best to make sure we all understand the material presented to us"
"[Lily is] able to explain concepts in a very clear manner (sometimes better than professor)"
MSc Thesis
The Effects of Maxillomandibular Advancement Surgery in the Treatment of Obstructive Sleep Apnea
Supervisor: Dr. Tim Wilson
What Is Obstructive Sleep Apnea?
As of May 2018, an estimated 100 million people have Obstructive Sleep Apnea (OSA) worldwide (1). OSA is a chronic and increasingly common sleep-related breathing disorder in which the airway is either partially or completely closed(2). Statistics Canada reported that 25% of the Canadian population are at high risk of developing OSA and in 2017, almost 7% of Canadians have been diagnosed with OSA, as compared to 3% reported in 2009(3,4). OSA can affect daily functions, and is associated with long-term health effects, such as cardiovascular disease, neurocognitive changes, diabetes, and early death (5-10).
What Is Maxillomandibular Advancement Surgery?
In cases of low compliance, ineffectiveness, or refusal of non-invasive treatment, surgery to reduce anatomical obstruction is considered. Other than tracheostomy, Maxillomandibular Advancement (MMA) surgery, in which the position of mandible and maxilla are advanced to increase the diameter of the airway, is considered to be the most effective surgical treatment for OSA (11–13). MMA is a safe, effective, & long-term treatment for OSA with a success rate of 96-100%(13-15). However, the optimal advancement distance has yet to be determined.
Why is this Research Important?
This work will inform surgeons performing MMA procedures of the optimal distraction distance that allows for minimal alteration of the patient’s appearance while still providing substantial increase in airway diameter and thus decreasing incidence of OSA episodes. To our knowledge, we are the first group to propose a advancement:volume relationship between distraction distance and airway volume , and the first group to assess the effects of MMA on both volumetric change and underlying tissue movement in an incremental fashion in a dose-response paradigm
What is the Project?
The research conducted explores the relationship between the distance the maxilla & mandible are advanced and the subsequent changes of the airway following an MMA surgery.
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The project has two specific aims:
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To determine the volumetric changes that occur concomitantly during incremental MMA within the airway
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To determine the movement of underlying tissues during incremental advancement
Aim 1
The first aim of this project will be accomplished in cooperation with oral and maxillofacial surgeons, who will perform the MMA surgery on cadaveric heads. In each head, the maxilla and the mandible are fitted with adjustable distraction devices (KLS Jacksonville USA). Once the distraction devices are in place, CT image scans (O-Arm, Miniapolis, USA) are performed at baseline (0mm advancement) and at each subsequent 2mm advancement interval until a maximum of 14mm. The maximum of 14mm will be used as the endpoint as distraction beyond 13mm is not utilized in clinic. The resulting 7 CT scans enable identification and calculation of volumetric alterations in the areas of interest of the pharynx. Using manual segmentation of the CT images and slice-by-slice volumes enable precise volumization at specific areas of the airway. This protocol has been previously utilized & optimized by our group.
Aim 2
The second aim is addressed through a slight modification of the protocol for aim 1. Prior to obtaining a baseline measurement, radiopaque microbeads will be implanted within the mouth and airway to specifically assess the movement of both tissues (e.g. hard palate) and significant structures (e.g. trachea). The translation of these microbeads will be measured to identify a relationship between volumetric change and tissue alteration during MMA surgery.
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